My car has had starting problems for a while now so I have upgraded the battery, inserted Iridium plugs and fitted the Magnacor red leads. They all needed replacing anyway so no problem there. All seemed ok but now, and this might be due to the cold, it's struggling to start again. Next thing to check is fuel pressure. First of all I am not sure if my M3W has had the fuel pump changed but whilst I find out I would like to check the fuel pressure via the Schrader valve. Can anyone recommend a reasonably priced one as it might only be ever used one.